For director Kim Jee-woon, humor is a basic element of films. And he says no matter how dark and moody it may seem, his new film ``A Bittersweet Life (Talkomhan Insaeng)’’ is no exception.

``This movie basically deals with relationship breakups resulting from small communication breakdowns,’’ Kim said during a news conference Monday after the preview screening of ``A Bittersweet Life.’’

Without calling it comedy exactly, sometimes audiences have to laugh at very serious or ironic situations, Kim said.

Kim has shown his unique morbid sense of humor in previous movies such as ``The Quiet Family,’’ a black comedy about a family who kill visitors to their cottage, ``The Foul King,’’ a comic drama about an amateur wrestler, and one horror contribution work for the omnibus film ``Three.’’

Kim is also behind ``A Tale of Two Sisters,’’ the psychological horror film that became a summer hit in 2003.

``A Bittersweet Life,’’ starring Lee Byung-hun from ``Everybody Has a Little Secret’’ and Shin Mina from ``Madeleine,’’ portrays the desperate and brutal revenge of Sun-woo (played by Lee) after he is expelled from his gang and comes close to being killed by his boss.

Lee Byung-hun is a hitman who falls for the girlfriend of his boss in the stylishly violent “A Bittersweet Life.” Conventional ideas of causation are put into doubt in director Kim Jee-woon's twist on film noire. ``A Bittersweet Life (Talkomhan Insaeng)'' is what Korean critics are describing as ``Action Noire.'' In it, he tweaks the traditional Korean gangster story line, presenting a work with film noire undertones and stylish cinematography.

Sun-woo (Lee Byung-hun) is a revenging dark angel dressed in black. Gang leader Kang (Kim Young-cheol) assigns Sun-woo, his right-hand man, to watch after his nubile girlfriend/professional cellist Hee-soo (Shin Mina) while he is away and find out about the other guy with whom he suspects she is messing around.

The plot is complicated by Sun-woo's existential decision to stray from the explicit instructions with which he is charged. He is cryptically told time and again to make good on a promise, but he never exactly know what that is.

Much of the action occurs in the long shadows the sprawling megapolis Seoul casts. Here, the gangsters wish they were too cool to be killed. No friend can really be trusted as the good guys are not so good and the bad guys can be down right evil. Importantly, the motivation of his tormentors is shrouded in mystery.

But the movie has been labeled ``action noire'' for a good reason. The stylistic ultra-violence of director Kim is superb. The creepy fisherman killer represents a unique Korean twist on the classic film noire villain. Our hero is not a good, good guy either, and I loved that about him. He is not only tough, but also a stone-face killer _ a tribute to both the director and actor's character interpretation.

After all, gangsters should fight to kill, and that means sometimes going for the knees and other joints, hitting low and dirty to take the guy out quick. In general, the fight scenes were creative. Watch for the face-dragged-across-the-cinderblock-wall scene, perhaps a first for cinematic violence.